In the low-cost backyard trampoline market, shipping costs are large in proportion to the cost of materials in products sold. The safety net systems that provide jumper enclosing protections included with almost all backyard trampolines sold today account for a large portion of shipping costs. Therefore, anything that greatly reduces the volume or weight of these safety net systems creates a large financial advantage through reduced shipping and storage expenses.
Additionally, a lightweight enclosure system has other advantages including: being easier for consumers to transport from a store, including being more likely to fit in their vehicle; being easier to install and setup as there are no heavy poles and support materials to assemble; being easier to take down, move, and reassemble at another more distant location. Also, at the end of its life, the discarded materials will produce less waist to process; and potentially results in fewer greenhouse gases being emitted from activities related to their manufacture and/or shipment.
Two United States patents, TRAMPOLINE OR THE LIKE WITH ENCLOSURE, U.S. Pat. No. 6,053,845 (referred to below as the “845” patent) and TRAMPOLINE OR THE LIKE WITH ENCLOSURE, U.S. Pat. No. 6,261,207 (referred to below as the “207” patent) represented a revolutionary change for the trampoline industry as a whole. Prior to those inventions, safety enclosures for use with home trampolines were practically non-existent. Many had proposed enclosure designs, but these were impractical or ineffective for a variety of reasons. This was the state of affairs even though millions of trampolines were in use worldwide, and the need to protect jumpers from fall-offs was well-known. For instance, a comprehensive study had found 80% of serious, hospitalized trampoline injuries resulted from falling off a non-enclosed trampoline. During this period, medical doctors, researchers, and the American Academy of Pediatrics were calling for a ban on their sale and use in schools and recreational and home settings. The problem was of such a concern that public schools banned trampolines, despite their popularity and health benefits and once iconic “trampoline parks” (commercial pay-to-bounce venues open to the public) went out of business. Trampolines were limited to home use and to specialty athletic training under supervision, in sports like gymnastics and diving, where use of spotting harnesses is common.
Despite the call for bans and removal of trampolines from virtually all public facilities, home use of trampolines continued to grow. However, injuries increased significantly, as well. The costs and risks remained. There was ample motivation to create an effective, affordable enclosure for home users, yet nobody had done it. If a way could be found to minimize fall-off injuries, it would've been utilized well before 1997. Efforts to develop fall protection devices were made, but resulted mostly in large, heavy, metal cages that surrounded the trampoline. For instance, one design described how to hand build a cage using plumbing pipes of metal or plastic, tied off with rope strapping, with the cage being strapped to the trampoline frame and/or ground.
These early structures were very heavy, cumbersome to construct, and excessively expensive to ship and store in warehouses and on store shelves. The higher mass of these enclosures was intentional in order to offset the force of an adult moving at speed and impacting them. A 200 lb. individual moving laterally against a wall produces very high linear momentum (mass×velocity). It was believed that Newton's Third law (typically recited as, “For every action, there is an equal and opposite reaction.”) required a high mass, high strength enclosure to repel a high momentum impact without failure or damaging the enclosure. However, high mass structures were so impracticable from a commercial standpoint that only a very limited number of enclosures were ever constructed or used with a trampoline, especially in the home market. Retailers were unwilling to stock and sell a product that took so much shelf and warehouse space and that was so heavy, bulky, expensive, and difficult to assemble. Prior to Publicover's inventions disclosed in the 845 and 207 patents, manufacturers and others in the industry could not find a way to design or produce an enclosure device that met these needs.
The Publicover patents 845 and 207 changed the calculation for the entire industry, radically altering the cost-benefit dynamics of enclosure production and sale. While the industry was seeking ways to lower costs (cheaper labor, etc.), the 845 and 207 innovation of attaching the net to shorter independent support poles and to the rebounding mat, directly or indirectly utilizing the rebounding surface to absorb impact forces, resulted in enclosures dramatically reduced in mass compared with the few enclosures that did exist at the time. The innovations were so profound that they were able to reduce average total mass of enclosures by approximately 50% over existing designs at that time, while still providing impact protection that exceeded all industry safety and reasonable performance standards. The commercial success of the 845 and 207 inventions is evident from the fact that sales went from virtually no enclosures being sold in 1997 to over a million sold and in use in the United States in just five or six years. Since then, the market has shifted further—today, effectively every trampoline sold worldwide has an enclosure, with the vast majority based on the 845 and 207 inventions.
Currently, mass-produced enclosures only marginally improve upon enclosure weight and package size by merely attempting to use thinner, weaker materials. This results in a significant degradation in performance and safety, producing far weaker enclosures that fail to or barely meet current ASTM standards (the voluntary US safety specifications), and results in enclosure pole and net components that fail within months or a few years. However, even these weaker devices still rely on the same design principles and inventions shown in 845 and 207. Over the past 20 years, no one has been able to improve upon those design principles in any significant way, especially in products for low-cost, mass-market sales.
Due to the rapid growth of online sales of trampolines, the need has grown to reduce the mass and packaging volume of the safety enclosure, while still retaining strength and performance. This need is even greater in the case of high-volume, low-margin consumer products, which make up an estimated 80% to 90% or more of all 14- to 15-foot circular enclosed trampolines (the most popular shape and sizes) produced and sold worldwide. These all-in-one (trampoline plus enclosure) systems are low-margin, low-cost products, generally selling for under $300 U.S. (in 2018 prices). By comparison, the average trampoline plus enclosure combo in 1998 sold for approximately $425 to $500. This simultaneous drop in retail price and increase in online sales has put tremendous pressure on the trampoline industry.
Over last 15 years, the number of trampolines sold in stores vs. online has shifted significantly. Today most low-cost, high volume trampolines are sold online with “free shipping” directly to the consumer. This shifts the freight cost burden to the retailers and manufacturers, putting further stress on margins. Shipping container or truckload quantities to a physical retail location are far more efficient and less costly than shipping individual products directly to an individual consumer. For example, based on standard freight and parcel rates, the cost to move a single enclosed trampoline system from the factory to a store shelf in the US is currently an estimated $35 to $65. From there, the consumer would buy and pick up the product, bearing the cost of getting it to his or her home. In contrast, moving a single enclosed trampoline system from the factory to an intermediary warehouse and then directly by delivery vehicle to a customer currently costs an estimated $125 to $225.
Most major parcel delivery services in the US now charge on the basis of the greater of the actual mass (weight), or the “DIM weight” (short for “dimensional weight,” and sometimes referred to as “volumetric weight”). The DIM weight is an estimated or theoretical weight of what an optimized package should weigh at an expected density. Products shipped in larger dimension packages and lower density cost more per pound, on average, than products shipped in smaller, more densely-packed cartons. Rising costs of shipping (including fuel) and storage have become an enormous expense for manufacturers and retailers. These factors have had a devastating effect on trampoline producers. Since 2005, many trampoline companies, both domestically and abroad, have either stopped producing trampolines or gone out of business due to these market pressures.
Despite the critical, long-felt need for lower weight, lower volume packaging, and consistent safety performance, no one has effectively reduced the weight or average packaging dimensions of enclosure products beyond the designs enabled by the 845 and 207 patents until the designs disclosed in this current application. The enclosure designs disclosed in this patent are approximately 40% to 60% lower in weight than other enclosure designs on the market for comparable size and performance. Generally, when similar construction materials are involved, the cost is directly proportional to the weight. So, for example, a 10% reduction in weight would be expected to reduce the overall cost to get the product to a consumer by approximately 10% (manufacturing cost, ocean freight, warehousing, and delivery charges). Thus, the new designs in this patent are expected to achieve as much as a 40% to 60% reduction in total cost of the enclosure as compared with nearly all current low-cost enclosures on the market.
To accomplish this result while also still being able to pass international product safety/performance standards (e.g., ASTM F381 and F2225 (United States), EN-71 (Europe), AS 4989 (Australia), etc.); and, still have a product that lasts many years was unexpected to the inventors on this patent. Until the inventions disclosed in this application, it was counter-intuitive to those skilled in the art to think an enclosure of such low mass would be able to pass all the standard tests and to perform over an acceptable number of years. Arched and others enclosure designs existed in the market for many years, but nobody expected they could successfully lower the mass and volume (and the expense) significantly and still meet safety standards, or it would've been accomplished prior to the disclosed devices.
In an advantageous example, the volume of the enclosure pole packaging disclosed in this application is reduced by 80 to 90% compared with typical mass-market enclosures.
The above discussion points to why the art disclosed in these drawings and specifications is so significant for the industry and for enclosed trampoline design, fabrication, shipment, storage and sales. The inventors in this patent did not believe it was possible to significantly the weight of enclosures based on the 845 and 207 patents while also significantly reducing the volume of packaging. The goal was simply to improve, to any small degree, the weight of the components (relative to system size) that had remained substantially constant for the past 20 years, and that no one had yet improved upon. Scores of new enclosure designs have been brought to market without achieving any real improvement in terms of reduced weight and packaging size, but also with acceptable performance. The disclosed devices will achieve significant cost-savings advantages over those products based on the 845 and 207 patents. The described device and its versions successfully reduces, on average, an approximate 50% of the required enclosure mass beyond what any earlier device has been able to achieve; and all with sufficient strength to exceed all current international safety and performance requirements.